This article addresses common issues encountered after an incorrect coding of module 09 (J519 – Central Electrics) in a Volkswagen Passat B7 equipped with halogen lights and separate DRLs and fog lights. We’ll explore how to diagnose and potentially rectify these issues using VCDS (VAG-COM Diagnostic System). The vehicle in question exhibits the following problems:
- Malfunctioning DRLs: The Daytime Running Lights (DRLs) are not illuminating when the light switch is in the auto position. Instead, other lights activate incorrectly.
- Dim Rear Position Lights: The rear position lights are significantly dimmer than they should be.
- Window Control Issues: Holding down the buttons on the remote key fob no longer consistently opens or closes all windows. This points to a potential coding issue affecting the convenience features.
Diagnosing the Problem with VCDS
An autoscan performed with a VCDS reveals fault codes within specific modules, providing valuable clues for troubleshooting. The provided autoscan highlights the following:
- Module 09 – Central Electrics (J519): This module shows a malfunction (Status: Malfunction 0010). This is the primary suspect given the nature of the reported issues. Further investigation into this module’s coding is necessary. Specifically, analyzing the long coding for module 09 is crucial to identify misconfigurations.
- Module 46 – Central Convenience: This module also registers a malfunction (Status: Malfunction 0010), likely connected to the reported window control problem. This malfunction may be directly related to the incorrect coding in module 09 or it may indicate a separate issue within the central convenience system.
- Fault Codes in Module 09 – Subsystem 1: Two specific fault codes were found relating to the stationary cornering lamps (left and right):
- 02235 – Stationary Cornering Lamp (Left) (M51) 010 – Open or Short to Plus
- 02236 – Stationary Right Cornering Lamp (Right) (M52) 010 – Open or Short to Plus These codes indicate an electrical issue with the cornering lamps, possibly a wiring problem or a faulty bulb. While seemingly unrelated to the DRL and window issues, they should be addressed.
- Fault Code in Module 46: A fault code related to the fuel tank flap control circuit was found:
- 00332 – Control Circuit for Tank Flap 007 – Short to Ground This code suggests a short circuit in the wiring controlling the fuel tank flap.
- Fault Code in Module 2E – Media Player 3: An unrelated fault was found in the media player:
- 03138 – Input AUX IN 009 – Open or Short to Ground This indicates a problem with the auxiliary input.
Understanding Long Coding in Module 09
The long coding in module 09 controls various vehicle features, including lighting and convenience functions. Incorrect values within this coding string can lead to unexpected behavior. The autoscan shows the current coding for module 09 as:
000800000000000000180080140081E403510088426D81606480C7200041
Decoding this hexadecimal string and comparing it to the factory default for the specific Passat B7 variant is crucial. This comparison will pinpoint the incorrect bits and allow for correction. Online resources, such as Ross-Tech’s VCDS forum, can provide guidance on interpreting and adjusting long coding.
Restoring the Original Coding
To restore functionality:
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Identify the Original Coding: Determine the factory long coding for your specific Passat B7 model using resources like the official VW service documentation or online forums dedicated to VCDS. The correct coding will vary depending on the vehicle’s equipment and options.
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Enter the Correct Coding: Using VCDS, navigate to module 09, access the long coding helper, and carefully input the correct hexadecimal string. Double-check each digit before saving.
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Clear Fault Codes: After entering the correct coding, clear all fault codes in the relevant modules (09 and 46) and verify that the issues are resolved.
Conclusion
Incorrectly coding module 09 can lead to a variety of problems in a Volkswagen Passat B7. Utilizing VCDS and understanding long coding is essential for diagnosing and rectifying these issues. Referencing reliable resources for the factory default coding for your specific vehicle is paramount for a successful repair. Remember to address all fault codes and thoroughly test the vehicle after implementing any coding changes. If you are unsure about any steps, consult a qualified automotive technician specializing in VW diagnostics.
